CVE-2021-29454
Prior to versions 3.1.42 and 4.0.2, template authors could run arbitrary PHP code by crafting a malicious math string.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (1.80%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
Smarty is a template engine for PHP, facilitating the separation of presentation (HTML/CSS) from application logic. Prior to versions 3.1.42 and 4.0.2, template authors could run arbitrary PHP code by crafting a malicious math string. If a math string was passed through as user provided data to the math function, external users could run arbitrary PHP code by crafting a malicious math string. Users should upgrade to version 3.1.42 or 4.0.2 to receive a patch.
- CVSS 3.1
- 8.8 HIGHCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- EPSS
- 1.80% probability · 78th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-74
- Affected
- smarty/smarty · debian/debian linux · fedoraproject/fedora
- Source
- security-advisories@github.com
EPSS 1.8% since 27 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
References
- https://github.com/smarty-php/smarty/commit/215d81a9fa3cd63d82fb3ab56ecaf97cf1e7db71Patch, Third Party Advisory
- https://github.com/smarty-php/smarty/releases/tag/v3.1.42Release Notes, Third Party Advisory
- https://github.com/smarty-php/smarty/releases/tag/v4.0.2Release Notes, Third Party Advisory
- https://github.com/smarty-php/smarty/security/advisories/GHSA-29gp-2c3m-3j6mThird Party Advisory
- https://lists.debian.org/debian-lts-announce/2022/05/msg00005.htmlMailing List, Third Party Advisory
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/BRAJVDRGCIY5UZ2PQHKDTT7RMKG6WJQQ/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/L777JIBIWJV34HS7LXPIDWASG7TT4LNI/
- https://packagist.org/packages/smarty/smartyProduct, Third Party Advisory
- https://security.gentoo.org/glsa/202209-09Third Party Advisory
- https://www.debian.org/security/2022/dsa-5151Third Party Advisory
- https://www.smarty.net/docs/en/language.function.math.tplVendor Advisory
- https://github.com/smarty-php/smarty/commit/215d81a9fa3cd63d82fb3ab56ecaf97cf1e7db71Patch, Third Party Advisory
- https://github.com/smarty-php/smarty/releases/tag/v3.1.42Release Notes, Third Party Advisory
- https://github.com/smarty-php/smarty/releases/tag/v4.0.2Release Notes, Third Party Advisory
- https://github.com/smarty-php/smarty/security/advisories/GHSA-29gp-2c3m-3j6mThird Party Advisory
- https://lists.debian.org/debian-lts-announce/2022/05/msg00005.htmlMailing List, Third Party Advisory
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/BRAJVDRGCIY5UZ2PQHKDTT7RMKG6WJQQ/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/L777JIBIWJV34HS7LXPIDWASG7TT4LNI/
- https://packagist.org/packages/smarty/smartyProduct, Third Party Advisory
- https://security.gentoo.org/glsa/202209-09Third Party Advisory
- https://www.debian.org/security/2022/dsa-5151Third Party Advisory
- https://www.smarty.net/docs/en/language.function.math.tplVendor Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.